[Boatanchors] Morse code - ECN and ACN?

[David Stinson]

For those who might be interested in
a railroad Morse take:

When telegraph lines were run along
the tracks for major railroads,
each switch or other "control point"
had a small shack or "bungalow" and
a "switchman" who had a sounder
on the telegraph line.
He listened for the Morse ID of
his "shack," which might be "EMJ"
(East Metro Junction), and the Morse
command, like "LSP" (Line Switch for Pass).
He would log the command and go
manually throw the switch, then key back
to Dispatch that the command was done.
A run of track from, say, Nashville to Atlanta,
was divided into "subdivisions," which were
further divided into sets of "control points"
which defined sets of switches or signals.

Each of  these sets of control points had an
individual DC-Level-Shift
(often about +/- 100V) telegraph pair back
to the Dispatcher, which
was called a "Code Line" (distinguishing it
from text message lines). Railroads might
have an in-house code of their own, but
most used American Morse.
Until the 1960s, many railroad telegraph
line maintainers or "linemen" still used
a hand telegraph key with connecting cord
which plugged-into a multi-jack panel back
at Dispatch- to hand-key orders to the switch
bungalows at the Control Points (switch
and/or signal).

Over the years, the hand-keyed systems
and switchmen were replaced by racks of
"stepper relays" which decoded the DC
commands, and "clockwork" relays to
send pre-formatted replies on the same
line.  Since this removed the need for
local switchmen and centralized switch
and signal controlling, it became known
as "Central Track Control" (CTC).

Later, the Morse from the Dispatcher
was interfaced to an analog tone system
which could be sent over Microwave
and handed- off to an interface rack at
a small track-side building.  The stepper
relays were replaced by digital interfaces
that read the coded DC level changes.
  The telegraph poles were abandoned
(along with all the winter storm damage
that comes with aerial lines) and a
new cable was buried next to the track.
Like the pole lines before,
they still carried switching DC levels,
using American Morse.

Even though these units were now
digital, they were often still called
"steppers" and the wire line was still
referred-to as a "code line."  and that
code, being sent via computer keyboard,
Microwave and digital interfaces was
still Railroad American Morse.

When I went to work with the railroad
in 2000, one of my duties was the care
of a large part of "Code Line 6."   I could
read the Morse keying by watching the
two DC level LEDs flash as commands
were sent over Code Line 6 to their
respective CTC points.  My last buried
DC code line using Morse was retired
in 2004.

Now, all our CTC is sent via computer
over microwave and 900 MC link.
That will soon be replaced by Positive
Train Control packet links.
It's all digital packets; the last of Morse
is gone. But to this day, the group of
CTCs for which I am responsible is called
"Code Line 6" and, once in awhile,
I will speak to a Signal Man almost
as grizzly old as me, and he will call
the computerized CTC interface
in his bungalow a "stepper."

GL OM ES 73 DE Dave AB5S

P.S. I was happy to see that last code
line cable be retired.  The gear was old
and the cause of many, many 2AM
call-outs.
A buried CTC cable is about as big around
as your forefinger.  Most railroad right-of-
ways are 50 feet on a side.  And that's
just the horizontal dimension.  The tool
used by crews boring a hole from one
side of the track to the other
is about the size of a beer can.
What are the odds of them hitting that
cable while boring?  If they didn't call
me to mark the cable (which, no matter
how much I fussed about it, they
rarely did), you'd make money betting
on them hitting it.   That alone
convinces me there are gremlins
in the world who delight in making
these unlikely things happen.

-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus